MADISON—U.S. District Judge Barbara Crabb in Madison Friday overturned Wisconsin's gay marriage ban, striking down an amendment to the state constitution approved overwhelmingly by voters in 2006.

Crabb did not stay her ruling but also did not immediately issue an order blocking the enforcement of the order, sparking a hasty debate among lawyers who had not even fully digested the decision on whether it meant that couples could immediately marry in the courthouses of Wisconsin.

Instead, Crabb asked the gay couples who had sued over the ban to describe by June 16 exactly what they wanted the judge to block with respect to the enforcement of the law. She said she would then address whether to stay her decision while the matter is on appeal.

Attorney General J.B. Van Hollen, a Republican, said that "current law remains in force" in Wisconsin and he would appeal the decision.

The case in the state comes amid a broad shift in public opinion about same-sex marriage.

Judi Trampf and Katy Heyning both work at UW-Whitewater. The Madison couple will have been together for 25 years in July. Trampf said she is ecstatic about the decision.

"We're extremely happy the judge ruled in our favor by ruling the amendment unconstitutional," Trampf said. "We are thrilled to possibly get married. We hope to get a marriage license as soon as possible."

Dane County Clerk Scott McDonell said he is in the process of reading through the decision. He could not determine yet whether he could begin administering marriage licenses today or whether he would need to wait.

McDonell said he and his staff were prepared if they learned marriage licenses could be administered today.

"We're ready to go," McDonell said.

"I will wait for instruction from the Wisconsin Department of Health Services," said Rock County Clerk Lori Stottler. "They are the ones who draft marriage licenses. They told us if this passed we would be given information on what we will be doing."

Milwaukee County Clerk Joe Czarnezki said: "Personally, I'm pleased she struck the ban down. It makes us proud to be in Wisconsin and a state that's standing up for marriage equality."

He said the phone has not stopped ringing with inquiries with questions and that he, too, is seeking advice.

"There are so many unknowns," Stottler said. "This is unknown territory for us. We will do what we have to to stay within state statutes."

In a statement, Van Hollen said that he was "encouraged by the District Court's refusal to issue an immediate injunction."

"We have seen the disruption to couples and families throughout the United States when courts have first allowed same-sex marriage only to have those marriages subsequently called into question by another court. I anticipate the United States Supreme Court will give finality to this issue in their next term," Van Hollen said.

"We are really into finishing the August ballot by next week," Stottler said. "It (the decision) will add to the stress of the office, but we will serve citizens as the law states. We will do what the state tells us to do."

Tamara Packard, a Madison attorney who supports the right to marry but was not involved in the case, said she read the decision to mean same-sex couples could immediately go courthouses to get married.

"People are likely running to their county clerks' office right now," she said.

Packard is also a court commissioner and she said she would expect to be presiding over weddings soon, possibly as early as Friday.

Crabb declared the ban unconstitutional but has not yet issued a formal injunction barring state officials from enforcing the marriage ban. But Packard said nothing prevents same-sex couples from getting married now.

"I think the clerk should comply with the declaration of unconstitutionality," she said. "I think the declaration is there —we have a constitutional right.

"I think she's declared what the law is and the clerks are required to follow the law Whether there's an order saying you must issue, I don't think that's very relevant."

Sen. Glenn Grothman (R-Campbellsport), who is running for the U.S. House in the 6th Congressional District, initially said Friday afternoon that he hoped that some county clerks would refuse to issue marriage licenses to gay couples despite the ruling. But he pulled back from that after a few minutes' reflection, saying that would be too radical a response.

"It's very sad that something approved by voters and represented as the law in every state for the first 200 years of the republic is all of a sudden declared unconstitutional," Grothman said. "…This will further the complete lack of respect that the public has for the judiciary."

Former Supreme Court Justice Janine Geske said she believes this is the first time a judge has struck down a Wisconsin constitutional amendment.

"The thing is, we don't have that many new constitutional amendments," Geske said Friday. Many of the state's amendments reflect the U.S. Constitution, she noted.

Crabb's ruling, Geske said, was in line with a raft of decisions by federal judges around the nation finding various bans on same-sex marriage unconstitutional.

"I'm not surprised," said Geske, who spent five years on the state Supreme Court and is now a professor at the Marquette University Law School.

Carl Tobias, a law professor at the University of Richmond, said Crabb's decision resembles others that have come out recently across the country.

"She's one of more than a dozen judges nationwide now who's done that," Tobias said.

U.S. Rep. Mark Pocan of Madison, who is openly gay, hailed the decision.

"The federal district court in Madison took another step toward ensuring full equality for every American. It is clear the growing momentum of support for marriage equality will put an end to discriminatory laws that treat LGBT couples as second-class citizens," he said in a statement.

A spokeswoman for Gov. Scott Walker, a Republican, did not immediately respond to a request for comment. His Democratic opponent in the governor's race, Mary Burke, was enthusiastic about the decision.

"Today is a great day for Wisconsin and committed couples who love each other across the state. Every loving couple should have the freedom to marry whomever they choose, and the fact that this freedom is now available in Wisconsin is something we all can and should be proud of," Burke said in a statement.

Democratic attorney general candidate Jon Richards also praised the ruling.

"I am overjoyed that our LGBT brothers and sisters will finally have the ability to marry in Wisconsin," he said. "Today is a joyous day for so many, and I am happy that all Wisconsin residents will be able to enjoy the right of marriage for the first time in our state's history."

Julaine Appling, executive director of Wisconsin Family Action, said the issue of same-sex marriage will ultimately be decided by the U.S. Supreme Court now that a string of federal judges have found gay marriage bans unconstitutional.

Appling's group helped lead the effort to put Wisconsin's ban in place and filed a friend-of-the-court brief in the case before Crabb.

"We are disappointed but not surprised," she said. "I'm mostly disappointed for the people of this state who spoke loudly and clearly in 2006. What a travesty of justice to have their vote overridden by the stroke of an appointed federal judge's pen. That is wrong. "

She said supporters of gay marriage do what her group did—persuade lawmakers to back a change to the state constitution in two consecutive legislative sessions and then have voters approve it in a statewide referendum.

By going to the courts instead, "They took the chicken's way out," she said. "They don't want a popular vote."

Nationwide, same-sex couples have the right to marry in 19 states and the District of Columbia. Judges in seven of the remaining 31 states have issued rulings striking down same-sex marriage bans, with those rulings stayed as they work their way through appellate courts.

In Wisconsin, voters in 2006 resoundingly approved the same-sex marriage amendment, 59% to 41%. Every county in the state except Dane voted for it.

But the most recent Marquette Law School poll, released May 21, found 55% of registered voters statewide now favor allowing gay marriage, while 37% oppose it and 6% say they do not know.

Last month, state Attorney General J.B. Van Hollen acknowledged he would not be surprised to lose the case. He asked the judge to immediately block her own decision if she does strike down the ban. Normally, lawyers wait until a judge rules before asking for a stay.

Julaine Appling, a representative of Wisconsin Family Action, said this week she hoped Crabb would consider the voters who supported the constitutional amendment when she makes her decision. Appling's group was instrumental in promoting the referendum to adopt the ban and more recently filed a friend-of-the-court brief in the case.

"I don't understand when 'We the People' became 'I the Judge,'" Appling said. "We hope that Barbara Crabb will make her decision keeping in mind that we the people define marriage in our state as between one woman and one man."

Clerks in Milwaukee, Dane, Waukesha and other counties say they were prepared for the ruling and for an expected stream of gay couples coming in to obtain marriage licenses.

Nick Crow of The Gazette and Daniel Bice and Georgia Pabst of the Milwaukee Journal Sentinel contributed to this report.